The proposed study will investigate the impact on school-age children of being the sibling of a gifted child. There is reason to suspect that the existence of a gifted child in a sibship tends to create a set of special stresses on the nongifted siblings, in part because of the adoption of unreasonable standards of and pressures for achievement, and in part because of greater parental focus on the identified gifted child. The consequences of these stresses are expected to include heightened anxiety (stress), increased behavior problems, decreased social competence, decreased perceived competence or self-esteem, lowered school achievement, decreased sibling intimacy, and greater submission to gifted sibling. At the same time, it is recognized that positive effects may accrue to the nongifted siblings, many of whom live in capable and resourceful families. To test these expectations, 240 pairs of siblings, ages 8-13 years, in two-child middle-class families will be identified in the Seattle area. In half the sample, one child will be enrolled in a program for gifted children; in the other group, neither child will be identified as gifted. Measures of intelligence and school achievement, responses by mothers and children to questionnaires, and a cooperation/competition game will be administered. The proposed study is a ground-breaker in an area in which research evidence is almost non-existent, a situation of considerable significance since the stresses, if they exist, may be creating considerable cost in a group of children expected to be of above average ability and promise.